Replaced EGR valve, Now getting P0172 / 5 "Too Rich"

[Bipeman]

Was pretty much living with a P0401 EGR Insufficient flow DTC and Too Lean (banks 1 and 2) DTC's for several months.
Had some other trouble with the truck sputtering and dying and didsome long needed maint including new fuel pump and filter, new air filter, cleaned Mass Airflow sensor (this seemed to fix the original problem), replaced plugs and wires. Truck then running OK but still getting P0401 and lean codes. Replaced EGR valve with a new Motorcraft part. P0401 and lean codes are now gone but have been replaced with P0172 and P0175 "System too Rich" DTC's.

Truck is running nicer than it has in a long time.

I don't understand how an EGR valve would cause a rich condition.

Scan shows LTFT's both minus 25, STFT's ranging from 0 to +14 (multiple tests).
Fuel Pressure 39.4
MAP 13.3
RPM 1900
IAT 78.8
MAF 2.5lb/min
ECT 199.4
TPS 19.6
Command EGR % 31.4
EGR Error % -32
BARO 29.2.

Will skip the Oxy Sensor data here but I think they look right. Can post if needed.

Thanks in advance!

 

[boominXplorer]

Clean the mass air again and make sure to use mass air cleaner and reset battery. Sometimes they learn bad data on first startup and throws everything off. If it continues with rich codes I'd replace the maf with an oem one or used one only. No aftermarket or reman ones.

 

[Bipeman]

Clean the mass air again and make sure to use mass air cleaner and reset battery. Sometimes they learn bad data on first startup and throws everything off. If it continues with rich codes I'd replace the maf with an oem one or used one only. No aftermarket or reman ones.

Thanks for the input. I cleaned the Mass Airflow sensor again yesterday but have not disconnected battery. Will do that and post results.

 

[Bipeman]

Hey boominXplorer.. Many Thanks! Reset (battery dixonnet) this AM.. drove about 100 miles today and the truck ran better than it has in months (probably years) with no check engine light. What a relief!

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